Antengene Announces Phase I Study of Anti-CD24 Monoclonal Antibody ATG-031

- The Phase I"PERFORM" studywill evaluate the safety and tolerability,pharmacology,immunogenicity,and preliminary efficacy of ATG-031 in patients withadvanced solid tumors or B-cell non-Hodgkin's lymphoma (B-NHL).

- ATG-031,discovered and developed in-house by Antengene,isthe world's first anti-CD24 antibody to advance to the clinic in oncology and Antengene's third drug candidate to enter clinical studies in the U.S.

SHANGHAI and HONG KONG,Sept. 21,2023 -- Antengene Corporation Limited ("Antengene" SEHK: 6996.HK),a leading commercial-stage innovative,global biopharmaceutical company dedicated to discovering,developing,and commercializing first-in-class and/or best-in-class medicines for hematology and oncology,today announced thata Phase I study of the best-in-class anti-CD24 antibody,ATG-031,has been approved by the Institutional Review Board (IRB) of The University of Texas MD Anderson Cancer Center in Houston,Texas,the United States.This clinical study,codenamed the PERFORM trial and led by MD Anderson,will be conducted in patients with advanced solid tumors or B-NHL.

The PERFORM trial is a first-in-human,multi-center,open-label,Phase I dose-finding study of ATG-031 in patients with advanced solid tumors or B-NHL. The study's primary objective is to evaluate the safety and tolerability of ATG-031 as a monotherapy,and determine the appropriate dose for Phase II studies. The secondary objective is to characterize the pharmacology,evaluate the immunogenicity,and assess the preliminary efficacy of ATG-031.

Dr. Amily Zhang,Antengene's Chief Medical Officer said,"We are excited about the progress being made with ATG-031. We look forward to further characterizing the safety,tolerability,and preliminary efficacy of ATG-031. We will begin enrolling patients for the study as soon as possible andplan to release the first batch of preliminary data from the study in 2024."

"Through committed work and unrelenting innovation,our R&D organization successfully advanced the ATG-031 program to the clinical stage in just three years,an achievement that has truly made us proud," said Dr. Jay Mei,Antengene's Founder,Chairman and CEO. "Based on the robust preclinical data of ATG-031,we are confident that the drug will continue to demonstrate its therapeutic potential in clinical studies. Moving forward,Antengene will press ahead the clinical development of its global rights programs with the aim of serving a broader population of patients."

About ATG-031

ATG-031 is a first-in-class humanized CD24 monoclonal antibody which inhibits the "don't eat me" signal and enhances macrophage-mediated phagocytosis of cancer cells. Tumor cells evade the surveillance of the human immune system by over-expressing "don't eat me" surface proteins that signal macrophages to prevent the detection and phagocytosis of cancer cells. CD24 (cluster of differentiation 24) is a prominent "don't eat me" signal that plays a significant role in tumor immune evasion by suppressing macrophage-mediated phagocytosis. Compared to CD47,another well-known "don't eat me" target,CD24 has a more restricted distribution in normal tissue and higher expression in cancerous tissue. In addition，unlike CD47，CD24 is not expressed on human red blood cells，allowing for a wider therapeutic window and minimal on-target-off-tumor toxicity as a CD24-targeted therapy.

As a novel innate immune checkpoint,CD24 orchestrates immune evasion through its interaction with the inhibitory receptor Siglec-10 (sialic-acid-binding Ig-like lectin 10) expresses on tumor-associated macrophages (TAMs). Preclinical data presented in 2023 at the American Association for Cancer Research Annual Meeting (AACR 2023) demonstrated that ATG-031 can specifically bind to CD24 with nM affinity and block the interaction of CD24 and Siglec-10. Furthermore,ATG-31 induces efficient phagocytosis with a picomolar EC50 and stimulates the pro-inflammatory cytokines production by macrophages.

About Antengene

Antengene Corporation Limited ("Antengene", SEHK: 6996.HK) is a leading commercial-stage R&D-driven global biopharmaceutical company focused on the discovery,development,manufacturing and commercialization of innovative first-in-class/best-in-class therapeutics for the treatment of hematologic malignancies and solid tumors,in realizing its vision of "Treating Patients Beyond Borders".

Since 2017,Antengene has built a pipeline of 9 oncology assets at various stages going from clinical to commercial,including 6 with global rights,and 3 with rights for the APAC region. To date,Antengene has obtained 29 investigational new drug (IND) approvals in the U.S. and Asia,and submitted 10 new drug applications (NDAs) in multiple Asia Pacific markets,with the NDA for XPOVIO® (selinexor) already approved in Mainland of China,Taiwan China,Hong Kong China,South Korea,Singapore and Australia.

Forward-looking statements

The forward-looking statements made in this article relate only to the events or information as of the date on which the statements are made in this article. Except as required by law,we undertake no obligation to update or revise publicly any forward-looking statements,whether as a result of new information,future events or otherwise,after the date on which the statements are made or to reflect the occurrence of unanticipated events. You should read this article completely and with the understanding that our actual future results or performance may be materially different from what we expect. In this article,statements of,or references to,our intentions or those of any of our Directors or our Company are made as of the date of this article. Any of these intentions may alter in light of future development. For a further discussion of these and other factors that could cause future results to differ materially from any forward-looking statement,please see the other risks and uncertainties described in the Company's Annual Report for the year ended December 31,2022,and the documents subsequently submitted to the Hong Kong Stock Exchange.

For more information,please contact:

Investor Contacts:

Donald Lung

E-mail: Donald.Lung@antengene.com

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